The 1960 Census Tract Summary File was created by merging the Census Bureau's 1960 3- and 8-block matrix tally tapes. The original 3-block file contains tract tallies derived from 100-percent questionnaire items. The 8-block tape contains tract data based on sample questionnaire items. Table 1 on the following page indicates the sampling fraction for each of the 63 tables contained in the data record. Note that some tables are repeated on both a complete-count and sample basis. Totals for these duplicate tallies will not necessarily agree.
Census Bureau source documents describing the original 3- and 8-block tapes may be obtained for the cost of reproduction by writing to the Central Users Service, Bureau of the Census, Washington D.C. 20233. Refer the 1960 Decennial Operations Division Technical Memoranda 29B (3-Block Matrix) and 29-T (8-Block Matrix) .

1Tabulated on a 100-percent basis in places of 50,000 or more inhabitants only. Elsewhere tabulated on a 25-percent basis only.2Rural farm and non-farm residence determined for persons in places of less than 50,000 inhabitants only.3Tabulated on a 20-percent basis in places of 50,000 or more inhabitants only. Elsewhere tabulated on a 5-percent basis only.4Tabulated for units in structures in places of 50,000 or more inhabitants only.5Tabulated in places of less than 50,000 inhabitants only.